Optimization of roselle beverage formulation using response surface methodology

Roselle beverage as a functional drink is rich in vitamin C and anthocyanin compounds. The aim of this work is formulation of roselle beverage. In this study roselle beverage formulations were prepared. Durability and physicochemical tests were investigated. Considering that roselle beverage is effective in treating diabetes, therefor it is necessary to use other sweeteners except sugar to decrease sugar from the formulation by replacing it with stevia. In order to optimize time and temperature conditions of aqueous extraction of roselle calyx, response surface methodology was used considering features such as anthocyanin content, vitamin C content, total solids and opacity of drink. The beverage formulation was done using the response surface methodology. Results suggested 85 °C for 10 min as the best conditions for aqueous extraction. The best product considering sensory evaluation, opacity and brix was including 1% stevia, 0.08 g/l Arabic gum, 95% extract and 0.9% sugar. Pasteurization and storage conditions significantly affected the total anthocyanin contents and vitamin C content of the product. The best condition of roselle beverage formulation can be used in industrial production.